Metasurface enhanced micro LED reverse design method based on Fourier mode and related equipment

Abstract

The invention discloses a metasurface enhanced micro LED reverse design method based on a Fourier mode and related equipment, and relates to the field of photoelectricity. The method comprises the following steps: realizing modeling of the internal optical behavior of the micro LED based on a vector FMM formula, and constructing a loss function; calculating an initial real value vector field and an imaginary part vector field, forming a complex Jones field based on the combination of the initial real value vector field and the imaginary part vector field, and optimizing the complex Jones field to obtain a vector field t; calculating the actual light extraction efficiency, and adjusting the geometrical shape and material parameters of the micro LED based on the error between the actual light extraction efficiency and the preset light extraction efficiency in the loss function; the internal optical behavior of the micro LED is modeled through a vector FMM formula, and the light extraction efficiency is remarkably improved in combination with loss function minimization.

Description

Technical Field

[0001] The present application relates to the field of optoelectronics, and in particular to a Fourier modal-based supersurface enhanced micro-LED reverse design method and related equipment. Background Art

[0002] Microscale light-emitting diodes (microLEDs) with lateral dimensions approaching 1 μm are of great interest in a variety of applications including augmented reality displays. In this context, high light extraction efficiency (LEE) is crucial due to the requirements for high brightness (e.g. for outdoor use) and the need to operate on battery power for long periods of time. It is desirable to apply methods such as inverse design to obtain LED designs with higher performance; inverse design is a powerful technique that automatically discovers the topology and shape of a design such that some objective function is minimized, suitable for creating metasurfaces that enhance LED LEE.

[0003] However, the light generated in micro-LEDs is spatially incoherent; spatially incoherent sources (such as spontaneous emission and thermal radiation) are extremely expensive to model by standard methods (requiring many independent simulations), which makes the inverse design of structures including incoherent sources computationally intractable. Summary of the invention

[0004] To solve the above problems, the present application discloses a Fourier mode-based metasurface enhanced micro-LED inverse design method, which models the internal optical behavior of the micro-LED through the vector FMM formula, and can accurately describe the distribution and propagation characteristics of the electric field at the material interface; combined with the loss function minimization process, the geometric shape and material parameters of the micro-LED can be automatically optimized, thereby significantly improving the light extraction efficiency (LEE).

[0005] The first technical solution adopted in this application is: providing a Fourier modal-based super-surface enhanced micro-LED reverse design method, comprising the following steps: Modeling the internal optical behavior of the micro-LED based on the vector FMM formula and constructing a loss function; maximizing the light extraction efficiency based on minimizing the loss function; An initial real-valued vector field is calculated based on the Jones direct method, and an imaginary vector field is calculated based on polarization characteristics. The initial real-valued vector field and the imaginary vector field are combined to form a complex Jones field, and the complex Jones field is optimized to obtain a vector field t; Modeling the distribution of non-periodic light sources in the micro-LED based on Brillouin area integration; An actual light extraction efficiency is calculated, and a geometric shape and material parameters of the micro LED are adjusted based on an error between the actual light extraction efficiency and a preset light extraction efficiency in the loss function.

[0006] The modeling of the internal optical behavior of the micro-LED based on the vector FMM formula includes: A local coordinate system is introduced to allow the Fourier decomposition of the direction-dependent permittivity; Optimize the continuity conditions of the displacement field for the tangent and normal components of the electric field.

[0007] Among them, the loss function is as follows: ; in, is the actual light extraction efficiency, is the preset light extraction efficiency.

[0008] The vector field t is obtained based on minimizing the loss function: ; in, To measure the vector field t and material parameters The matching loss function is: Represents the vector field t and material parameter gradient The coupling relationship between Represents a vector field The square of the gradient in the xy-plane, Represents a vector field The square of the gradient in the xy-plane; ; is the geometry of the candidate vector field, based on Get the loss function Minimize the vector field t.

[0009] The modeling of the non-periodic light source distribution based on Brillouin area integration includes: Decompose a large unit cell into multiple small unit cells for simulation; The simulation results of all small unit cells are averaged to eliminate non-physical interference effects.

[0010] The formula for calculating the light extraction efficiency is as follows: ; in is the energy emitted by the dipole, The energy emitted by the dipole extracted from the micro-LED.

[0011] Wherein, adjusting the geometric shape and material parameters of the micro LED comprises: Automatic adjustment of geometry and material parameters based on gradient descent or genetic algorithms; The actual light extraction efficiency is recalculated after each adjustment and it is evaluated whether the error has been reduced.

[0012] Among them, the loss function takes into account light extraction efficiency, luminous uniformity and directionality at the same time, and constructs a comprehensive loss function based on a weighted method , the specific formula is as follows: ; in, is the loss function related to light extraction efficiency, is the loss function related to luminous uniformity, is the directionality-related loss function, , and is the weight coefficient.

[0013] The second technical solution adopted in the present application is: an electronic device is provided, which includes: a memory and a processor coupled to each other, and the processor is used to execute program instructions stored in the memory to implement the Fourier mode-based super-surface enhanced micro-LED reverse design method as described in any of the above items.

[0014] The third technical solution adopted in the present application is: providing a computer-readable storage medium, wherein the computer-readable storage medium stores program data, and the program data can be executed by a processor to implement the Fourier mode-based supersurface enhanced micro-LED reverse design method as described in any of the above items.

[0015] Due to the adoption of the above technical solution, the present application has at least one of the following beneficial effects compared with the prior art:

[0016] 1. The internal optical behavior of micro-LEDs is modeled through the vector FMM formula, and the light extraction efficiency is significantly improved in combination with loss function minimization.

[0017] 2. Vector FMM allows Fourier decomposition of direction-dependent permittivity and optimizes the continuity conditions of the displacement field for the tangent and normal components of the electric field; this not only improves modeling accuracy, but also significantly increases computational speed.

[0018] 3. The complex Jones field formed by the combination of the generated initial real-valued vector field and the imaginary vector field, after optimization, lacks discontinuities and zero points, ensuring that the local coordinate system represented by the Fourier basis is more stable and has the best convergence.

[0019] 4. Through the Brillouin regional integration method, the large unit cell is decomposed into multiple small unit cells for simulation, and the results are averaged and approximated, which effectively eliminates the non-physical interference effect; this method makes the modeling of complex light source distribution feasible and avoids the computational bottleneck in traditional methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them: Figure 1 A schematic flow chart of an embodiment of a Fourier-modal-based metasurface enhanced micro-LED reverse design method provided in this application; Figure 2 A schematic diagram of calculating light extraction efficiency using the Jones direct FMM method according to an embodiment of the present application; Figure 3 This is a schematic diagram of the structure of an embodiment of a computer device of the present application; Figure 4 This is a schematic diagram of the structure of an embodiment of a computer-readable storage medium of the present application. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It will be appreciated that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some but not all structures related to the present application are shown in the drawings. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the art without making creative work are within the scope of protection of the present application.

[0022] The terms "first", "second", etc. in this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the steps or units listed, but also includes steps or units that are not listed, or also includes other steps or units inherent to these processes, methods, products or devices.

[0023] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0024] Due to the high computational complexity, insufficient modeling tools, optimization difficulties and non-physical interference, traditional micro-LED design methods are difficult to effectively use inverse design to improve light extraction efficiency. In order to solve the above problems, this application provides a Fourier modal-based metasurface enhanced micro-LED inverse design method, which models the internal optical behavior of micro-LEDs through the vector FMM (Fourier modal method) formula, and significantly improves the light extraction efficiency by minimizing the loss function. Figure 1 As shown, Figure 1 The flowchart of an embodiment of a Fourier modality-based metasurface enhanced micro-LED reverse design method provided in this application includes the following steps:

[0025] Step S11: Modeling the internal optical behavior of the micro-LED based on the vector FMM formula and constructing a loss function; in the micro-LED design, the vector FMM formula is used to model the displacement fields of the tangent and normal components of the electric field; for example, the micro-LED contains a metasurface structure with a complex interface, and the vector FMM can accurately describe the behavior of the electric field at the interface by introducing a local coordinate system. Compared with the traditional FMM method, the convergence speed of the vector FMM is increased by several times, and the modeling accuracy is higher.

[0026] The light extraction efficiency is maximized based on minimizing the loss function. The loss function directly quantifies the gap between the actual light extraction efficiency and the target value, so that the optimization process always focuses on the core goal of improving the light extraction efficiency. The light extraction efficiency of the optimized device can be more than doubled, greatly improving the overall performance of the micro LED.

[0027] Step S12: Calculate the initial real-valued vector field based on the Jones direct method, and generate a real-valued vector field represented in the local coordinate system by directly calculating the polarization characteristics of the electric field; the generated real-valued vector field has the following characteristics:

[0028] Lack of discontinuities: Compared with the Normal method, the Jones method produces a smoother vector field and avoids numerical errors caused by discontinuities.

[0029] Missing Zeros: There are no zero regions in the vector field, which improves the stability of subsequent calculations.

[0030] The imaginary vector field is calculated based on the polarization characteristics. According to the polarization characteristics of the light source inside the micro-LED (such as the polarization direction of the dipole radiation), the imaginary vector field corresponding to the initial real-valued vector field is calculated; the imaginary vector field reflects the phase information of the electric field in the time domain and is an important component of constructing the complex Jones field.

[0031] The initial real-valued vector field and the imaginary vector field are combined to form a complex Jones field, which can fully describe the spatial distribution and time evolution characteristics of the electric field. The complex Jones field is optimized to obtain the vector field t, which has the following characteristics: lack of discontinuities and zero points, excellent performance in the local coordinate system represented by the Fourier basis, and good convergence.

[0032] The FMM of the Jones method has the best convergence and performs well in dealing with complex electromagnetic field problems; the optimized vector field t can quickly converge to the optimal solution, greatly shortening the calculation time. The optimization process of the vector field t fully considers the characteristics of the non-periodic structure in the micro-LED and can accurately describe the optical behavior under complex boundary conditions.

[0033] Step S13: Modeling the non-periodic light source distribution in the micro-LED based on Brillouin area integration; the light source in the micro-LED is distributed non-periodically, and the traditional FMM method assumes that the light source and structure are periodic, which may lead to non-physical interference effects (such as false interference fringes or abnormal energy distribution); the method based on Brillouin area integration effectively eliminates these interference effects, making the simulation results more realistic and reliable.

[0034] In the reverse design of micro-LEDs, the light source distribution needs to be accurately modeled to optimize the geometry and material parameters; the light source distribution model generated by the Brillouin area integration method can be directly used in the reverse design process to provide reliable input data.

[0035] Step S14: Calculate the actual light extraction efficiency, and adjust the geometry and material parameters of the micro LED based on the error between the actual light extraction efficiency and the preset light extraction efficiency in the loss function; Based on the error feedback mechanism, automatically adjust the geometry and material parameters through the optimization algorithm, avoiding the inefficiency and subjectivity in traditional manual design, and the automated process significantly improves the design efficiency; By continuously evaluating the error and making adjustments, a closed-loop feedback mechanism is formed to ensure that the final design is reliable and stable.

[0036] In summary, the Fourier mode-based metasurface enhanced micro-LED reverse design method of this embodiment includes the following steps: modeling the internal optical behavior of the micro-LED based on the vector FMM formula and constructing a loss function; maximizing the light extraction efficiency based on minimizing the loss function; calculating the initial real-valued vector field based on the Jones direct method, calculating the imaginary vector field based on the polarization characteristics, the initial real-valued vector field and the imaginary vector field are combined to form a complex Jones field, and the complex Jones field is optimized to obtain the vector field t; modeling the distribution of non-periodic light sources in the micro-LED based on the Brillouin area integral; calculating the actual light extraction efficiency, and adjusting the geometric shape and material parameters of the micro-LED based on the error between the actual light extraction efficiency and the preset light extraction efficiency in the loss function; modeling the internal optical behavior of the micro-LED through the vector FMM formula, and significantly improving the light extraction efficiency in combination with minimizing the loss function.

[0037] In one embodiment, modeling of the internal optical behavior of a micro-LED based on a vector FMM formula includes: A local coordinate system is introduced to allow Fourier decomposition of direction-dependent permittivity. In the geometric structure of the micro-LED, a local coordinate system with a unit vector is introduced. The local coordinate system is tangential and perpendicular to the material interface. Using the local coordinate system, Fourier decomposition of direction-dependent permittivity (i.e., anisotropic material properties) is allowed. That is, the tangent component and the normal component of the electric field are Fourier expanded separately to accurately describe the propagation and distribution characteristics of the electric field in different directions.

[0038] Optimize the continuity conditions of the displacement fields of the tangent and normal components of the electric field; ensure that the tangent component of the electric field meets the boundary conditions at the material interface; ensure that the displacement field of the normal component of the electric field meets the boundary conditions at the material interface.

[0039] By introducing a local coordinate system to allow Fourier decomposition of the direction-dependent permittivity and optimizing the continuity conditions of the displacement field for the tangent and normal components of the electric field, the vector FMM formulation achieves accurate modeling of the internal optical behavior of micro-LEDs. This approach not only improves convergence, but also improves modeling accuracy, adapts to complex boundary conditions, and enhances computational efficiency.

[0040] In one embodiment, the loss function is as follows: ;in, is the actual light extraction efficiency, To preset the light extraction efficiency; the calculation process of an embodiment is described in detail below: Setting target light extraction efficiency =80%, initial design actual light extraction efficiency =40%.

[0041] Use the gradient descent method to adjust the geometry and material parameters of the micro-LED; recalculate the actual light extraction efficiency after adjustment to obtain the second actual light extraction efficiency =55%, and the loss function value calculated for the second time is 25%.

[0042] Continue iterating and optimizing, and after multiple adjustments, the actual light extraction efficiency finally reaches =78%, the final loss function value is 2%, and the optimization ends.

[0043] In this embodiment, the optimization is terminated when the final loss function value is 2%, and the convergence threshold is 2%. In other embodiments, the convergence threshold may take other values ​​without any limitation. It should be noted that, in other embodiments, the number of optimizations may also be used as a criterion for terminating the optimization. For example, in one embodiment, the optimization is terminated after the number of optimizations reaches 10 times.

[0044] In this embodiment, by defining the loss function , the gap between the actual light extraction efficiency and the target value can be quantified, and based on this, the geometry and material parameter optimization of micro-LEDs can be guided. This method can not only significantly improve the light extraction efficiency, but also has multiple advantages such as automation, high efficiency and high reliability, providing strong technical support for the practical application of micro-LEDs.

[0045] In one embodiment, the vector field t is obtained based on minimizing the loss function: ; in, To measure the vector field t and material parameters The matching loss function is: Represents the vector field t and material parameter gradient The coupling relationship between Represents a vector field The square of the gradient in the xy-plane, Represents a vector field The square of the gradient in the xy-plane; ; is the geometry of the candidate vector field, based on Get the loss function Minimize the vector field t.

[0046] The following is a detailed description of the steps to select the vector field that minimizes the loss function: Define an initial candidate vector field , the candidate vector field can be generated randomly; The candidate vector field and material parameters Substitute into the loss function formula and calculate the current loss function value ; Use optimization algorithms to adjust candidate vector fields , so that it gradually approaches the optimal solution; in each iteration, according to the gradient information of the loss function, To reduce the loss function value; Recalculate the loss function value after each iteration And evaluate whether the convergence condition is met. When the convergence condition is met, the final candidate vector field That is the optimal vector field t.

[0047] By minimizing the loss function, it is ensured that the final vector field t can accurately reflect the influence of material parameter distribution on light propagation; Represents the vector field t and material parameter gradient The coupling relationship between them enhances the ability to describe complex electromagnetic field behaviors; and The term limits the magnitude of changes in the vector field in the xy-plane and avoids unreasonable fluctuations.

[0048] In one embodiment, modeling of a non-periodic light source distribution based on Brillouin area integration includes: Decompose a large unit cell into multiple small units for simulation. Decompose a large unit cell containing a non-periodic light source into multiple smaller units (sub-unit cells), each of which contains local light source distribution information. Each sub-unit cell can be individually modeled for electromagnetic fields, and the electric field distribution inside it can be calculated using the Fourier modal method (FMM) or other numerical methods. This decomposition method can reduce computational complexity and retain the main characteristics of the light source distribution.

[0049] The simulation results of all small unit cells are averaged and approximated to eliminate non-physical interference effects; after completing the simulation of each sub-unit cell, the results of all sub-unit cells are collected and averaged and approximated using the Brillouin regional integration method. The specific steps are as follows: The electric field distribution of all subcells is integrated.

[0050] The non-physical interference effects are eliminated through average approximation processing, and finally a global non-periodic light source distribution model is generated.

[0051] Accurate modeling of non-periodic light source distribution is crucial for the design of micro-LEDs. The Brillouin area integration method can better capture the spatial distribution characteristics of the light source and avoid the errors caused by the periodic assumption in traditional methods. In the reverse design of micro-LEDs, the light source distribution needs to be accurately modeled to optimize the geometry and material parameters. The light source distribution model generated based on the Brillouin area integration can be directly used in the reverse design process to provide reliable input data.

[0052] like Figure 2 As shown, Figure 2 FIG. 1 is a schematic diagram of calculating light extraction efficiency using the Jones direct FMM method according to an embodiment of the present application.

[0053] In one embodiment, the formula for calculating the light extraction efficiency is as follows: ;in, is the energy emitted by the dipole, is the energy emitted by the dipole extracted from the micro-LED, is the weight factor, r represents the position of the dipole, p represents the polarization mode, represents the direction of the wave vector.

[0054] Determine the position r and characteristics (such as polarization mode p and wave vector direction) of all dipoles inside the micro-LED )Dipole is the basic unit of the light source in micro-LED, and its distribution and characteristics determine the overall light extraction efficiency.

[0055] For each dipole, calculate its polarization in all polarization modes p and wave vector directions The total energy of emission ; Using a flat panel monitor or other measurement tool, record the dipole emission energy successfully extracted from the micro-LED .

[0056] Assign weight factors to different polarization modes or directions according to specific application requirements ; for all dipole positions r, polarization modes p and wave vector directions , the extracted energy and the total emitted energy are weightedly summed up respectively to calculate the light extraction efficiency LEE.

[0057] Taking into account the position of the dipole, polarization mode and wave vector direction, the light extraction efficiency of the micro-LED can be comprehensively evaluated; the calculation results of the light extraction efficiency can be directly used in the reverse design of the micro-LED to optimize the geometry and material parameters to improve performance.

[0058] In one embodiment, adjusting the geometry and material parameters of the micro-LEDs includes: Automatically adjust the geometric shape and material parameters based on the gradient descent method or genetic algorithm; the gradient descent method is suitable for continuously differentiable objective functions, and updates the parameters by calculating the gradient information of the loss function; the genetic algorithm is suitable for complex nonlinear problems and searches for the optimal solution by simulating the natural selection process.

[0059] After each adjustment, the actual light extraction efficiency is recalculated and whether the error is reduced is evaluated; if the error is reduced, the adjustment is continued; if the error is not reduced, other parameter combinations are tried; if the error meets the convergence condition, the optimization is stopped; otherwise, the iteration is continued.

[0060] In one embodiment, the loss function takes into account light extraction efficiency, luminous uniformity and directionality at the same time, and constructs a comprehensive loss function based on a weighted method. , the specific formula is as follows:

[0061] in, is the loss function related to light extraction efficiency, is the loss function related to luminous uniformity, is the directionality-related loss function, , and is the weight coefficient.

[0062] Weight coefficient , and The setting can be flexibly adjusted according to specific needs to highlight the importance of certain performance indicators; in one embodiment, is 0.6, is 0.3, is 0.1; it should be clear that this application does not limit the specific value of the weight coefficient, but the weight coefficient must meet the normalization condition, that is, .

[0063] By constructing a comprehensive loss function and considering light extraction efficiency, luminous uniformity and directionality in a weighted manner, multi-objective optimization of micro-LEDs can be achieved. This method is not only flexible and accurate, but also can automatically generate the optimal design solution, significantly improving design efficiency and reliability. This technology provides strong support for the design of high-performance micro-LEDs, especially in complex multi-objective optimization scenarios.

[0064] For the above embodiment, the present application provides a computer device, see Figure 3 , Figure 3This is a schematic diagram of the structure of an embodiment of a computer device of the present application. The computer device includes a memory and a processor, wherein the memory and the processor are coupled to each other, the memory stores program data, and the processor is used to execute the program data to implement the steps of any embodiment of the above-mentioned Fourier mode-based metasurface enhanced micro-LED reverse design method.

[0065] In this embodiment, the processor may also be referred to as a CPU (Central Processing Unit). The processor may be an integrated circuit chip having signal processing capabilities. The processor may also be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0066] The method of the above embodiment can be implemented in the form of a computer program, so the present application proposes a computer readable storage medium, see Figure 4 , Figure 4 This is a schematic diagram of the structure of an embodiment of a computer-readable storage medium of the present application. The computer-readable storage medium stores program data that can be run by a processor, and the program data can be executed by the processor to implement the steps of any embodiment of the above-mentioned Fourier mode-based metasurface enhanced micro-LED reverse design method.

[0067] The computer-readable storage medium in this embodiment may be a medium that can store program data, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, or may be a server that stores the program data. The server may send the stored program data to other devices for execution, or may execute the stored program data by itself.

[0068] In the several embodiments provided in this application, it should be understood that the disclosed methods and devices can be implemented in other ways. For example, the device implementation described above is only illustrative, for example, the division of the modules or units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0069] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0070] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0071] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A Fourier modal-based supersurface enhanced micro-LED reverse design method, characterized in that: The steps include: Modeling the internal optical behavior of the micro-LED based on the vector FMM formula and constructing a loss function; maximizing the light extraction efficiency based on minimizing the loss function; An initial real-valued vector field is calculated based on the Jones direct method, and an imaginary vector field is calculated based on polarization characteristics. The initial real-valued vector field and the imaginary vector field are combined to form a complex Jones field, and the complex Jones field is optimized to obtain a vector field t; Modeling the distribution of non-periodic light sources in the micro-LED based on Brillouin area integration; An actual light extraction efficiency is calculated, and a geometric shape and material parameters of the micro LED are adjusted based on an error between the actual light extraction efficiency and a preset light extraction efficiency in the loss function.

2. The Fourier modal-based metasurface enhanced micro-LED reverse design method according to claim 1, characterized in that: The modeling of the internal optical behavior of the micro-LED based on the vector FMM formula includes: A local coordinate system is introduced to allow the Fourier decomposition of the direction-dependent permittivity; Optimize the continuity conditions of the displacement field for the tangent and normal components of the electric field.

3. The Fourier modal-based metasurface enhanced micro-LED reverse design method according to claim 1, characterized in that: The loss function is as follows: ； in, is the actual light extraction efficiency, is the estimated light extraction efficiency.

4. The Fourier modal-based supersurface enhanced micro-LED reverse design method according to claim 3, characterized in that: The vector field t is obtained based on minimizing the loss function: ； in, To measure the vector field t and material parameters The matching loss function is: Represents the vector field t and material parameter gradient The coupling relationship between Represents a vector field The square of the gradient in the xy-plane, Represents a vector field The square of the gradient in the xy-plane; ； is the geometry of the candidate vector field, based on Get the loss function Minimize the vector field t.

5. The Fourier modal-based metasurface enhanced micro-LED reverse design method according to claim 1, characterized in that: The modeling of the non-periodic light source distribution based on Brillouin area integration includes: Decompose a large unit cell into multiple small unit cells for simulation; The simulation results of all small unit cells are averaged to eliminate non-physical interference effects.

6. The Fourier modal-based metasurface enhanced micro-LED reverse design method according to claim 1, characterized in that: The formula for calculating light extraction efficiency is as follows: ； in is the energy emitted by the dipole, The energy emitted by the dipole extracted from the micro-LED.

7. The Fourier modal-based metasurface enhanced micro-LED reverse design method according to claim 1, characterized in that: Adjusting the geometry and material parameters of the micro-LED includes: Automatic adjustment of geometry and material parameters based on gradient descent or genetic algorithms; The actual light extraction efficiency is recalculated after each adjustment and it is evaluated whether the error has been reduced.

8. The Fourier modal-based metasurface enhanced micro-LED reverse design method according to any one of claims 1 to 7, characterized in that: The loss function takes into account light extraction efficiency, luminous uniformity and directionality at the same time, and constructs a comprehensive loss function based on a weighted method , the specific formula is as follows: ； in, is the loss function related to light extraction efficiency, is the loss function related to luminous uniformity, is the directionality-related loss function, , and is the weight coefficient.

9. An electronic device, characterized in that: The electronic device includes: a memory and a processor coupled to each other, and the processor is used to execute program instructions stored in the memory to implement the Fourier mode-based super-surface enhanced micro-LED reverse design method as described in any one of claims 1-8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores program data, and the program data can be executed by a processor to implement the Fourier mode-based supersurface enhanced micro-LED reverse design method as described in any one of claims 1-8.

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